Power drive for flat knitting machines



2 Sheets-Sheet l May 12, 1931. J. G. MULLER POWER DRIVE FOR FLAT KNITTING MACHINES Filed Jan. 11, 1930 May 12, 1931. J. G. MULLER POWER DRIVE FOR FLAT KNITTING MACHINES Filed Jan. 11, 1930 2 Sheets-Sheet 2 Patented May 12, 1931 E? ii;

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POWER DRIVE FOR FLAT KNITTING MACHINES Application filed January 11, 1930, Serial No.

The fiat knitting machines hitherto in use are mostly driven by hand, as the mechanical driving means for these machines, of which a large number exists, do not offer sufiicient advantages for small works to warrant their being introduced.

A mechanical driving arrangement is for example known, in which the sliding rod to be connected with the carriage receives a reciprocating movement by a pull rope, the ends of which are fastened to the sliding rod and which is wound between the fixation points around a drum, the periodically alternating rotary movement of which is eiiectet by the engagement of a clutch sleeve with the claws of beltpulleys, the changing being effected by a setting lever acting on stops displaceable in the sliding bar.

A driving arrangement is also known, in which the carriage is connected with a clutch, which is disengaged by adjustable stops from one side of theendless pull element and at the same time coupled with the other side running in the opposite direction, whereby the disengagement and simultaneous engagement of the carriage is effected without the interposition of other driving means.

Gears are also known for producing a reciprocating motion by means of an endless chain or the like running continually in the same direction over reversing wheels, in which a sliding element is moved backwards and forwards by means of a catch fi'ted on the chain, which element carries along by means of a clutch a carriage the travel of which is to be shorter than that of the sliding element and can be adjusted as required by means of cams.

All these constructions are however open to the objection, that the flat knitting machines which with hand drive run easily and quickly with cam reverse free from shocks, are too slow and impractical with power drive, as they either have the same running speed for a narrow piece of work as for work extending over he whole width of the machine, or the reverse of the cam is more or less jerky or uneven,as it pass-es'from one direction to the other suddenly and without transition stage, which renders the attaining of 420,166, and in Germany February 16, 1927.

high working speeds impossible, especially with narrow work, owing to the light construction of the hand fiat knitting machines.

These requirements are considered in the drive according to the invention and further, machines fitted therewith can be quickly changed over from power drive to hand drive and reversely. The width of the fabric can be easily adjusted without changing any elements, and further irregular wear of the needle bed is prevented, when knitting narrow fabric on wide machines in that the working points on the machine may be changed as desired. The drive according to the invention enables, owing to its absolutely smooth reversal of the carriage, a considerable increase of the working speed which, in conjunction with the increased runningspeed, results in a considerably higher output with narrow fabric without the machine being put under considerable strain.

Taking these facts into consideration, the drive according to the invention consists essentially oithe arrangement of a known end less driving chain, rotating continually in the same direction in a vertical plane, the reversing movement being effected by a driving wheel-segment mounted on a horizontal pin of the runner, which segment engages in its up )er and lower position respectively, with the teeth in the driving chain and, on reaching the end of the variable travel of the runner, transfers from one length of chain to the other, turning through 180.

With this object in view a crank guide is arranged in frontof the driving wheel segment, in the sliding part of which guide a crank pin engages, which is mounted on aguide disc rigidly connected with the driving wheel segment, whereby the reversing operation acts on the pull chain in such a manner, that its movement is gradually slowed down in the extreme positions and the speed of movement in the new direction gradually taken up again. The reduction of the 7 moving speed is efiected in that the runner carries the crank-guide held in its central position by springs arranged on both sides, as also two buliers which, upon striking against the stops regulating the fabric width cause anent 14 and moved. to and fro in its actu.

a reversing of the driving wheel segment and of the crank-guide connected therewith. Further, the connection between the reversing device and the knitting machine cam is here produced by a horizontal pull chain, which influences the movement of the knitting machine cam by a differential transmission so, that the cam moves at an increased speed as compared with the runner, the direction of movement of the cam being indicated ahead by an. indicator arranged on the crankguide.

An embodiment of the invention is illustrated by way of example in the accompanying drawings in which:

Fig. 1 shows the con'iplctc diagramnnitic elevation.

Fig. shows the arrangement in top plan view.

Fig. 3 is side ele ation, of the runner or carriage with the reversing device.

Fig. 4 a top plan view of Fig.

Fig. 5 is a section through the slide bars.

The drive for hand operated fiat knitting machines consists of a wooden plate 1, fastened behind the machine on or to the machine frame. On the wooden plate 1 two bows 2 and 3 are fixed, on which slide bars t and and hearings for two sprocket wheels 7 and 8 of an endless driving chain 6 running in a vertical plane, are arranged. The sprocket wheel 8 is adapted to be displaced in known manner for tensioning the driving chain 6 by means of stretchin screws, whereas the sprocket wheel 7 is keyed.

A runner 12 is situated in the slide bars 4 and 5, which runner is guided on four ir ing shoes 12, 12", 12", 12 in the grooves of the slide bars. The runner 12 has a 13 (Figs. 3 and 4), projecting horizontallv between the two ch n sides of the dririin); chain 6. On the pin 13 a driving is rotatably mounted so the in central positions its teeth cngz' in the upper or only in the driving chain (1' and. on ma ,1 passes, from one side of chain to in such a. manner that, as sooi; as the arrangement in pi n.

tooth engages in, one side of chain, the last tooth leaves the other side of chai aide 18 is mounted in front of the driving wh cl seg:

=11 central position in horizontal direction by means of a crank pin 19 mounted on the guide disc 16 rigidly connected with the driving wheel segment 14. The crank pin 1?) lies exactly in the pitch circle of the tooth segh the d ri vment and engages in a slipper 20 located in the crank-guide 18. The crank-guide 18 is held in its central position by means of two spiral spring" and put under slight tension, thereby arresting the driving wheel ient 14. (in the ends of the guide rods 23, 2 1 of the cra11l-t-gnide 1S loose chain wheels 811C 26 are arranged. A pull chain 25), guided at the front on the outer side of the box surrounding the device and carrying in the centre a catch for the itt-ing machine cam 31, runs in a horizontal plane over sprocket wheels 25 and 26 and two further sprocket wheels 27 and 28 arranged on the right and on the left of the bows 2, 3. This pull chain is guided in such amanner that the knitting machine cam has positively doublc the speed of the runner 12.

The upper slide bar +1 is provided with bows or holes 32, the distance between which corresponds with the pitch of the chain. Two work width adjusters 33 and 84; are arranged on the slide bar -11. These adjusters are held by means of spring pins in the bores or holes 32 of the slide bar 1, whereas buffer springs 5 and 36 are arranged on the right and on he left on an angle piece on the runner 12 exactly at the height of the work width ad- An indicator 3? is also fastened on 1 's. and 4-), which nidicator moving ahead is turned at the end of knitting a course by means of the angle arms 38 and 39 in the actual direction of movement of the lock.

The operation is as follows :-After engaging the friction clutch 11, the driving chain 6, and with it the runner 12, is moved in the direction of the arrow by neans of the sprocket wheel 7, the chain 6 is stretched over and in engagement with a portion of the circumference of the driving wheel segment 14:. At the same time the crank guide arranged in front of the guiding disc 16 in the runner 12, is carried along and the pull chain 29, carrying the catch 30 for the knitting machine cam 31 and rumiing in a horizontal direction over the sprocket wheels 21', 26, 27 and is moved at double the speed. \Vhen the l'iuil'er springs 35 and 36 fastened on the runner 12 reach one of the work width adjusters 33 and 84, previously set to a certain working width, the runner 12 stops. At this instantthe driving chain (5, which continues rrnining in the sax-no direct-ion, turns the d riving wncel segn'ient through 90 and displaces thereby tl e crank-guide 18 until the teeth of the driving segment 14; engage in the other side of the chain. At the movement of the crank-guide one of the spiral springs 21 or 22 is always stretched in lateral direction in the same direction, whereby the reaction of the knitting machine cam 31 has no effect on the runner 12, so that the reversing is effected when the runner is standing still. Moreover the spiral springs 21 and 22 act on the knitting machine cam 31 according to the tension and previous adjustment in the case of reciprocating machines. After a further rotation through 90, the crank-guide 18 again reaches its central position and is carried along by the runner 12 in the opposite direction.

The drive is mounted in a case of wood or sheet metal, fastened behind the machine on the machine table. This protecting case serves at the same time as a stand for the bobbins so that the power drive does not take up any additional space.

I claim 1. A power drive for flat knitting machines, particularly such with short carriage, in which a runner is moved backwards and forwards by means of an endless chain or the like running over sprocket wheels continually in the same direction, comprising in combination with said driving chain and said runner, a horizontal pin on said runner, atoothea driving wheel segment on said runner, said teeth adapted to engage in the two end positions respectively with said driving chain and, on the runner attaining a certain adjustable length of travel, to pass from one side of said chain to the other turning thereby through 180.

2. A power drive as specified in claim 1, comprising in combination with the driving chain, the knitting machine cam and the driving wheel, a crank-guide arranged in front of said driving wheel segment, a slipper in said crank-guide, a crank pin engaging in said slipper, a guide disc rigidly connected with said driving wheel segment carrying said crank pin adapted at the reversing movement to act on the chain of the knitting machine cam so that in the end position tl e movement of said chain is gradually slowed down and the moving speed in the opposite direction gradually increased.

A power drive as specified in claim 1, comprising in combination with the runner and the driving wheel segment, a crank-guide carried by said runner. springs bearing against said guide adapted to hold said guide in its central position, buffers on said runner adapted to effect the reversal of said driving wheel segment and of said crank-guide, and work width adjusters adapted to determine the working width.

41. A power drive as specified in claim 1, comprising in combination with the knitting machine cam and the pull chain, a crankguide, guide bars on said guide, chain wheels loosely mounted on the end of said guide bars, a bow on each end of said crank guide, a pull chain, the ends of which are fastened on said bows, a transmission acting on said pull chain adapted to impart an increased speed to said knitting machine cam carried along by said chain, as compared with that of said runner.

In testimony whereof I atiix my signature.

JOHANN so'r'rrmnn MULLER. 

